Radio shield for engines



Jan. 30, 1934. R. CHlLTON RADIO SHIELD FOR mamas Filed June 8, 1933 l Il 10 W I F 4/ I I6 16 I l/ 26 [J 15 6 Z7 27 25 19 I l l I -19 1 2g fig.21 Z1 I X 11 29 :6 e6 89 14 I I6 16 31 I 1 I 31 I, 10' 15 14 I In? I3-30 1 17 I 16' 17 16 I 7? 12 14 i I INVENTOR ROLAND CHILTON BY I ATTORNEYPatented Jan. 30, 1934 UNITED STATES- 1,945,021 7 mmo SHIELD non ENGINESRoland Chilton, Ridgewood, N. J., assignor to Wright AeronauticalCorporation, a corporation of New York Application June s, 1933. SerialNo. 614,818

' 10 Claims. (01.123-148) the magneto distributors, high tension wiringand spark plugs. The particular phase of shielding with which thisinvention is concerned is that which covers the high tension wiring fromthe' magnetos to the point or points whence the wires are led therefromto the spark plugs of the individual cylinders.

Current types of aircraft engines to which shielding is applied;comprise a substantially circular crankcase having mounting lugsextending therefrom, which are bolted to a substantially circularmounting ring carried by theaircraft structure, the ring being ofslightly larger diameter than the bolt circle of the mounting lugs;

. the ring and bolt circle are held to as small a diameter as possibleto conserve space. The

crankcase forward .of the mounting lugs carries the engine cylinderswhile, on the rear of the crankcase, rearward of the mounting ring andlugs, a. plurality of engine accessories, including high tensionmagnetos for ignition, are grouped.

It is essential that all, or nearly all, of such accessories be confinedwithin aspace having a diameter less than that of the mounting ring, inorder that the engine may be removed or installed as a unit, without thenecessity of removing certain accessories and reinstalling them afterthe engine has been mounted. This calls for careful arrangement of theengine accessories, and usually results in very small clearance betweenthe crankcase, the accessories, and the mounting 40 ring. I

In the past, radio shielding for an engine as above outlined includedforwardly facing metal elbows attached to the tops of the shieldedmagnetos, and from these elbows, trunk flexibly shielded cables extendedforwardly, between the mounting ring and the crankcase, to divide andpass to the engine cylinders}, Alternatively, the trunk cables have beenconnected to ring wire manifolds on the crankcase near the engine mount.This construction; due to the proximity of the front magneto face to themounting ring, usually requires removal of the shielding elbows andcables from the magnetos to accomplish removal orinstallation of theengine. As the magnetos are usually aldjustably rockably mounted on theengine to allow for adjustment of spark timing, previous shieldinginstallations have sometimes made necessary the movement of the magnetosfrom their properly adjusted positions in order to remove or install anengine. Obvious- 0 ly, this procedure is most inconvenient andexpensive, as it subsequently requires retiming of the ignition andre-synchr'onizing of the two magnetos.

Since the engine carburetor is frequently 5 mounted at the top of thecrankcase, the ignition wire manifold must be interrupted on either sideof the carburetor, and, since each of the engine cylinders is wired toeach magneto, ignition wiring must be threaded from each magneto, around7 the carburetor, to each side of the ignition wire manifold. By theolder construction, a neat shielding installation is diflicult ofaccomplishment, flexible shielding must be used at points where theshielding may be damaged, and thread- 5 I ing of the wiring,particularly in engines having a large number of cylinders, becomesincreasingly difiicult.

My invention provides a shielding arrangement wherein the ignitionwiring is carried rearward-. ly from each magneto through a solidmetallic conduit or manifold, ,the latter being provided with acrossover between the magnetos rearward of the engine mounting ring, sothat solid trunk manifolds may be led to each side of the engine tocontain only-those ignition wires which terminate at the cylinders onthose respective sides of the engine. By the rigid mounting of thecrossover conduit with relation to the engine crankcase, "and by theprovision of telescoping joints between the crossover conduit and themagnetos, individual timing adjustment of the magnetos may be effectedwithout aifecting the balance of 'the shielding and wiring and withoutaffecting the ease with which the engine may be mounted or dismounted.Further, the solid manifolds and conduits are sturdy and resistant toabrasion which might occur by careless handling of the engine. Myconstruction also permits relatively easy replacement of wiring, sinceall wiring is, carried in the crossover element and the trunk manifoldsfrom the magnetos to those points in the manifolds whence the individualwires are led to the engine cylinders.

, Objects of the invention are to provide an im 05 proved shielding forengines; to provide solid shielding manifolds mounted on the engine; toprovide means for allowing magneto timing adjustment without interferingwith engine remova1 or the shielding elements; and to provide a radioshielding manifold attached toand forming a part of the engine, wherebyremoval of all or part thereof is unnecessary in mounting or dismountingthe engine from an aircraft. It will be apparent that the principles ofmy invention may be embodied in shielding for other types of engines,such as V type or in-line type.

Further objects will be apparent in reading the specification andclaims, and in considering the drawing, in which Fig. 1 is a plan of therearward portion of an engine crankcase carrying the shielding of thisinvention, and Fig. 2 is a rear elevation of the same structure.

The rear crankcase section 10 of an engine, of substantially circularshape, projects rearwardly through an engine mounting ring 11. Lugs 12extending outward from the crankcase, bridge the space between the caseand the ring, and are adapted to be attached thereto by clips 13encircling the ring tubing, the bolts 1% passing through the clips andlugs. On the rear face of the crankcase 10, a pair of magnetos 15 aremounted for angular adjustment, by means of studs 16 engaging slottedopenings 17 in the magneto flanges 18. Each magneto is provided with ametallic distributor shield 19 having a rearward opening 20 within whichan elbow 21 is fitted for slight angular adjustment. A'crossover conduit22 is provided with oppositely facing inlets 23 adapted totelescopically engage the open ends of the elbows 21. Packing nuts 24are provided to effect a snug joint between the conduit 22 and theelbows 21. The conduit 22 is held rigidly on the crankcase 10, thetelescopic joints between the conduit 22 and the elbows 21 allowing forindividual timing adjustment of the magnetos 15 without affecting theposition of the conduit. Forwardly extending angular outlets 25 on theconduit 22 connect with conduits 26, by suitable joints 27, saidconduits 26 extending forwardly, around a carburetor 28, to be connectedas at 29 to shielded manifolds 30 which partly encircle the crankcase 10beneath the mounting lugs 12. The manifolds 30 are provided with aplurality of outlets 31, conveniently spaced, through which individualwires may pass to the engine cylinders. An example of the wiring isindicated wherein a wire 34 passes from the left magneto, and a wire 35passes from the right magneto, through the conduit 22, and thencethrough the left hand outlet 25, the left hand conduit 26, the left handmanifold 30, through a pair of outlets 31 ,to one of the left handengine cylinders. Similarly, wires 36 and 37 pass, one from eachmagneto, through the right hand manifold syste'm to a right handcylinder. Thus, only those wires for right hand cylinders lead from theright hand outlet of the crossover conduit 22, and only wires for lefthand cylinders lead from the left hand outlet of the crossover conduit22. The wiring is greatly simplified over the old system, avoiding sharpbends and allowing all elements to be firmly anchored to the engine.

By the use of the rigid manifolds 26, a fixed clearance distance X isallowed between them and the mounting ring 11, which clearance, inprevious structures either did not exist or was subject to variationwhen the magnetos were adjusted through the angle Y, since the manifoldsmoved with the magnetos.

While I have described my invention in detail in its present preferredembodiment, it will be obvious to those skilled in the art, afterunderstanding my invention, that various changes and modifications maybe made therein without departing from the spirit or scope thereof. Iaim in the appended claims to cover all such modifications and changes.

What is claimed is:

1. A radio shielding for an engine having angularly adjustable magnetoscomprising a wire encasing manifold, a crossover wire encasingconnection telescopically connecting said magnetos, and shieldingconduits connecting said crossover connection to said manifold.

2. The combination with an engine having shielded magnetos mounted fortiming adjustment of a telescopic cross over ignition wire shieldconnecting said magneto-shields.

3. The combination with an engine having shielded magnetos mounted fortiming adjustment, of a telescopic crossover ignition wire shieldconnecting said magneto shields, said telescopic crossover shield havingoutlets, and shielding conduits connecting to said outlets.

4. The combination with an engine having rockably mounted shieldedmagnetos, of a twin outlet crossover shielding telescopically connectedwith said magneto shields, and shielding conduits connected to saidcrossover connection, the whole adapted for adjusting movement of saidmagnetos without movement of said connection or conduits.

5. The combination with an engine having movably mounted magnetosprovided with radio shields, of a rigid crossover connectiontelescopically connecting the magneto shields and provided with suitableoutlets and shielding conduits connecting said outlets.

6. The combination with a radial cylinder engine having a pair ofoscillatable magnetos mounted on the rearward end thereof, of ashielding conduit fixed to the engine, and members movably carried onsaid magnetos and adapted to telescope within said conduit, said membersand conduit being adapted to house the wiring emanating from saidmagnetos.

7. The combination with a multi-cylinder engine having a pair ofoscillatable magnetos mounted thereon in spaced relation, of a metallicshielding conduit mounted on said engine, said conduit having an openingadjacent each magneto. and'hollow members carried by each magneto andtelescopically engageable with said con- ,25 duit to permit adjustmentof said magnetos with respect ,to said engine and conduit, said membersand conduit being adapted for the housing of ignition wiring.

8. The combination with a multi-cylinder engine having a magneto mountedfor limited angular adjustment on said engine, of an elbow carried bysaid magneto and a metallic shielding conduit mounted on said engine,said elbow and conduit being arranged for telescopic engagement topermit relative adjustment therebetween, and said elbow and conduitbeing adapted for the housing of ignition wiring.

9. The combination with an engine having a crankcase adapted to becarried by a mounting ring, wherein said ring is in substantiallyannularly spaced relation to said case and wherein a magneto is carriedfor angular adjustment on said crankcase, of a metallic radio shieldingconduit mounted on said case and'passing between said ring and saidcase, said conduit having a: movable shielding connection with saidmagneto to permit adjustment of said magneto relative to said conduit. pv

10. The combination with a multi-cylinder en- 15c gine having a pair ofmagnetos mounted thereon, of radio shielding means comprising an elbowmounted on each magneto, a substantially straight conduit connectingsaid elbows, said conduit having a pair of central angled openings, anda pair of metallic shielding manifolds registering with said angledopenings, each said manifold being adapted to house ignition wiring

